fix: materialize stationary yutong daily mileage

go/vehicle-gateway/cmd/stats-backfill/main_test.go

@@ -323,6 +323,95 @@ func TestQueryRealtimeLocationLastRowsBuildsYutongSourceFromPeer(t *testing.T) {
 	}
 }
 
+func TestQueryRealtimeLocationLastRowsCanCarryStationaryYutongMileage(t *testing.T) {
+	db, mock, err := sqlmock.New()
+	if err != nil {
+		t.Fatalf("sqlmock.New() error = %v", err)
+	}
+	defer db.Close()
+
+	loc := time.FixedZone("Asia/Shanghai", 8*3600)
+	currentEventTime := time.Date(2026, 7, 19, 6, 5, 42, 0, loc)
+	mock.ExpectQuery("(?s)SELECT.*l\\.event_time.*l\\.total_mileage_event_time < \\?.*COALESCE\\(l\\.speed_kmh, 0\\) = 0").
+		WithArgs("YUTONG_MQTT", "2026-07-19", "2026-07-19", "2026-07-19").
+		WillReturnRows(sqlmock.NewRows([]string{"vin", "peer", "event_time", "total_mileage_km"}).
+			AddRow("LMRKH9AC9R1004099", "mqtt://yutong/ytforward/shln/2", currentEventTime, 24245.0))
+
+	rows, err := queryRealtimeLocationLastRows(context.Background(), db, config{
+		Location:        loc,
+		StationaryCarry: true,
+	}, envelope.ProtocolYutongMQTT, "2026-07-19")
+	if err != nil {
+		t.Fatalf("queryRealtimeLocationLastRows() error = %v", err)
+	}
+	sourceRows := rows["LMRKH9AC9R1004099"]
+	if len(sourceRows) != 1 {
+		t.Fatalf("rows = %d, want 1", len(sourceRows))
+	}
+	if !sourceRows[0].TS.Equal(currentEventTime) || sourceRows[0].TotalKM != 24245 {
+		t.Fatalf("stationary carry row = %#v", sourceRows[0])
+	}
+	if err := mock.ExpectationsWereMet(); err != nil {
+		t.Fatalf("sql expectations: %v", err)
+	}
+}
+
+func TestAddRealtimeLocationFallbackStationaryCarryUsesTrustedHistoricalBaseline(t *testing.T) {
+	mysqlDB, mysqlMock, err := sqlmock.New()
+	if err != nil {
+		t.Fatalf("mysql sqlmock.New() error = %v", err)
+	}
+	defer mysqlDB.Close()
+	tdDB, tdMock, err := sqlmock.New()
+	if err != nil {
+		t.Fatalf("td sqlmock.New() error = %v", err)
+	}
+	defer tdDB.Close()
+
+	loc := time.FixedZone("Asia/Shanghai", 8*3600)
+	vin := "LMRKH9AC5R1004133"
+	currentTS := time.Date(2026, 7, 19, 10, 20, 20, 0, loc)
+	previousTS := time.Date(2026, 7, 17, 8, 49, 55, 0, loc)
+	sourceKey := stats.SourceKeyForSource(envelope.ProtocolYutongMQTT, "", vin, "mqtt", "PLATFORM", "yutong")
+	mysqlMock.ExpectQuery("(?s)FROM vehicle_realtime_location l.*l\\.event_time.*l\\.total_mileage_event_time < \\?").
+		WithArgs("YUTONG_MQTT", "2026-07-19", "2026-07-19", "2026-07-19").
+		WillReturnRows(sqlmock.NewRows([]string{"vin", "peer", "event_time", "total_mileage_km"}).
+			AddRow(vin, "mqtt://yutong/ytforward/shln/4", currentTS, 55451.0))
+	mysqlMock.ExpectQuery("(?s)SELECT latest_total_mileage_km, latest_event_time.*FROM vehicle_daily_mileage_source").
+		WithArgs(vin, "2026-07-19", "YUTONG_MQTT", sourceKey).
+		WillReturnRows(sqlmock.NewRows([]string{"latest_total_mileage_km", "latest_event_time"}).AddRow(55466.0, previousTS))
+
+	aggregates := map[string]*metricAgg{}
+	added, err := addRealtimeLocationFallbackAggregates(context.Background(), mysqlDB, tdDB, config{
+		TDengineDatabase: "lingniu_vehicle_ts",
+		DateFrom:         "2026-07-19",
+		DateTo:           "2026-07-19",
+		Protocols:        []envelope.Protocol{envelope.ProtocolYutongMQTT},
+		Location:         loc,
+		StationaryCarry:  true,
+	}, aggregates)
+	if err != nil {
+		t.Fatalf("addRealtimeLocationFallbackAggregates() error = %v", err)
+	}
+	if added != 1 || len(aggregates) != 1 {
+		t.Fatalf("added=%d aggregates=%d", added, len(aggregates))
+	}
+	for _, agg := range aggregates {
+		if agg.FirstKM != 55466 || agg.LatestKM != 55466 {
+			t.Fatalf("stationary km range = %v -> %v", agg.FirstKM, agg.LatestKM)
+		}
+		if agg.QualityStatus != stats.QualityOK || agg.QualityReason != stats.QualityReasonStationaryCarry {
+			t.Fatalf("quality = %s/%s", agg.QualityStatus, agg.QualityReason)
+		}
+	}
+	if err := mysqlMock.ExpectationsWereMet(); err != nil {
+		t.Fatalf("mysql sql expectations: %v", err)
+	}
+	if err := tdMock.ExpectationsWereMet(); err != nil {
+		t.Fatalf("td sql expectations: %v", err)
+	}
+}
+
 func TestAddRealtimeLocationFallbackAggregatesUsesHistoricalBaseline(t *testing.T) {
 	mysqlDB, mysqlMock, err := sqlmock.New()
 	if err != nil {